"Fixed" one of my GTX1080 graphics card

[jonsig]

Good day.
I "repaired" one of my old 1080´s card. Game Rock(palit)
The card was behaving oddly, it could work for few hours then it would artifact the image and finally it would get detected but black screen. Windows booting in the background.

After checking for common faults , i ran MATS.
With following resault:
=== MEMORY ERRORS BY SUBPARTITION ===
SUBPART READ ERRORS WRITE ERRORS UNKNOWN ERRS
------- ----------- ------------ ------------
FBIOA0            0            0            0
FBIOA1            0            0            0
FBIOB0            0       659544        0

I replaced the suspicious GDDR5X chip, but the error did persist, with same count of errors. So i guessed the memory controller,substrate or the traces / BGA.
So there was one thing i could do before i would bin the card.
I stripped the card, of thermalpads. etc. and put the card in ultrasonic cleaner i can use at my workplace. After that i warmed the card slightly with temperature adjusted heat gun and let amtech flux flow under the chip from all sides holding the card vertically. Then i put kapton tape around the GPU with thermalprobe.
Put the pcb on pre-heater and let it warm up to around 180°C . After heat soaking, then used Ryoby heat gun ,set to 270°C to warm up the die carefully to around 225¨C .. Pinched the die with tweezers to confirm that BGA balls are in fluid state. And after ten seconds let the card slowly cool down to room temperatre.

I did not think this was a long term fix, but i have stressed the card a lot with furmark and run it through multiple heat cycles but it´s solid. But for how long ?

The ultrasonic cleaner seems to destroy solder oxidation, but of course.. i have no idea if this is gpu substrate problem. Many claim this is 100% substrate problem, but i think board flexing is large culprit . I ´m wondering if skipping the ultrasonic cleaning and proper flux application limits success of gpu "cooking" ?

[testpoint1]

if you use the real amtech flux (not chinese amtech faked flux) 559, then clean it is no problem, I just assume the GPU chip is OK, as usual, before you use BGA, please check and test the VRAM chip's pin within PCB.

[thm_w]

I doubt you will find hard evidence.
I would tend to guess ultrasonic cleaner won't have much impact unless you believe there was water damage involved. Although, I wonder if it were a power connection you would get some arcing and carbon build up?

Rossman refuses to do it, saying full re-ball is the only true fix (fair enough). Others will do it without even using flux, fix may last for months or years. Look at various PS3, PS4, XBOX, etc. posts.

https://www.ifixit.com/Guide/Temporarily+Repair+a+Lost+Cause+Graphics+Card+by+Heating+it+up+in+an+oven/2240

[jonsig]

The card has been subjected to extreme loads now for two weeks and lot of thermal cycling, no errors so far.

I used this fake amtech flux while i was poor student in technical collage it was handed to the local recycling center.
Topnik zel is my no.1 general flux. It´s easy to clean and handles high heat for long time. Then i use only genuine amtech for BGA.

I´ve fixed a bunch of pascal cards and given to charity. I find dead gpu problems quite rare, except for older cards like maxwell 2.0

[jonsig]

More than two months of heavy use, and the GTX1080 shows no signs of failure or instability.

Guess there is luck in play here, or this is simply more effective way of reflowing the solder attached to the GPU.

[testpoint1]

as usual, the chip layer problem by BGA rework "fix" it maybe can use 6 months.

[jonsig]

Yes, this is interesting. I will surely report the card status after ~4months. But then GPU shortage is not a concern,.. hopefully. And no one cares anymore 
However i have yet to see any solid proof of this chip layer problem being the culprit for most GPU issues. I can imagine mechanical stress / damage is overlooked. Older high end cards look miniature in size compared to modern mid- tier cards.

[MathWizard]

If it worked this good so far, but starts happening again, what about fully removing and desoldering/resoldering the chip, it remove the old crusty solder ? Or do you actually need a template or mask type thing, just to get the solder balls positioned right, before the chip goes back on, and re-flowed ?

I have an old, broken GPU that works for 1-2min, then sounds like it's overheating, and shuts down. Some day for fun I need to get it back in a PC, w/ a DMM and scope on it. But 1st I need to map out the circuits better, never had much luck w/ it so far.

[thm_w]

If it worked this good so far, but starts happening again, what about fully removing and desoldering/resoldering the chip, it remove the old crusty solder ? Or do you actually need a template or mask type thing, just to get the solder balls positioned right, before the chip goes back on, and re-flowed ?

I have an old, broken GPU that works for 1-2min, then sounds like it's overheating, and shuts down. Some day for fun I need to get it back in a PC, w/ a DMM and scope on it. But 1st I need to map out the circuits better, never had much luck w/ it so far.

Thats called re-balling, which is much much harder than reflowing.
You need solder balls, stencil, and preheater, hot air for tools. The cost of those is not the main concern, its the labor involved.

https://www.aliexpress.com/item/32842413556.html

[jonsig]

I have an old, broken GPU that works for 1-2min, then sounds like it's overheating, and shuts down. Some day for fun I need to get it back in a PC, w/ a DMM and scope on it. But 1st I need to map out the circuits better, never had much luck w/ it so far.

Most likely the gpu is kaput in your case. Those are the worst types of failures i have encountered.
In few cases this could attribute to faulty VRAM, and extremely rare cases faulty Vcore-VRM controller (phase distrotion).
Thats why 99% of gpu repair videos involve "not detected" cards.

The GTX1080 is still alive. I lend it to my friend, who is addicted to video games, and is experimenting with mining
Im fully aware of the labor regarding GDDRX reballing, i´m not wasting whole day to reball obsolete GPU 

[DavidAlfa]

Good job! This is the classic reflow hack.
Could last a day, a week, or years, but it's worth trying if you have the proper tools and skills to do it without burning the board!
Once the bga ball cracks, the internals will oxidize.
Flux doesn't make miracles, migh be able (or not) to fix that, depending on how bad it is.
Lead-free solder seems to make a really hard, crusty shell when it oxidizes, I had some 10-year-old BGAs than had been boucing around the box unsealed, the iron wouldn't melt the balls at 380C, it felt like trying to melt iron.
I made few passed over very fine sandpaper to expose the fresh solder, then the iron melted the balls, but the crusty parts remained, floating everywhere on top of the melted solder.

[jonsig]

Card still alive and kicking in the hands of computer addict. No issues so far.


updated 20.7.2022
still used by pc gaming addict.